Bill Gates, the founder of Microsoft, unveiled his vision of a networked future yesterday with the announcement of a technology platform which he claimed would put the world's largest software company at the centre of the internet for consumers and businesses.

In launching .NET - pronounced dot-net - a networking platform that is to act as a foundation to many new services, Mr Gates made no mention of his company's long-running legal battle with the US government yesterday.

However, the new product's emphasis on integration could reignite the interest of regulators concerned about the company's monopoly of personal computers extending to all devices accessing the net. Earlier this month the Seattle-based company was found to have broken US anti-monopoly laws and was told it should be broken up.

Microsoft.NET will act as a software platform that allows users to access their personal information from any device, anywhere in the world.

As an example of its power, the company unveiled a prototype of a new product yesterday named the Tablet PC, a roughly A4-sized flat machine described as combining the "visual qualities of a magazine with the handiness of a notebook and power of a PC".

The new technology will incorporate voice and handwriting recognition technology as well as processing ordinary text. In a presentation to journalists and analysts at the Microsoft campus yesterday, Mr Gates described the platform as the most significant development for the group since Windows, some 15 years ago.

Windows is now used on more than 90% of the world's PCs. The long-awaited and already delayed announcement represented the fruition of years of research and billions of dollars in investment.

Mr Gates said: "It's a bet the company thing. We are putting our resources behind this."

In its fight with the courts, Microsoft has consistently argued that its ability to provide a base language for computers benefits consumers. The government has argued that it has simply used its dominance of the world's operating systems to stamp out competition in other areas. Mr Gates said yesterday that in the "new era" it was vital to have a single platform which could be understood by any machine. The new software, he said, would "allow individual building blocks to be combined together".

He brushed aside the idea that yesterday's launch was as significant as the launch of the Internet Explorer browser, integrated with Windows in 1995 and which ultimately led to the initial government legal action. "It is a new concept of something running out in the internet, out in the cloud, working on your behalf," he said.

Senior Microsoft executives were keen to stress that other developers would be encouraged to provide new services to be used on .NET - just as they had for Windows. They said the company was dependent on hardware manufacturers developing the necessary smart phones and other intelligent devices.

Steve Ballmer, Microsoft's chief executive, who is to lead the plans to implement the new platform, said: "The internet revolution must now move to its next stage: ensuring that the ocean of information and resources that is out there actually work together.

"By creating a unified platform through which devices and services co-operate with each other, Microsoft will unleash a new wave of developer opportunity and creativity that will move us to a level of power and simplicity."

Microsoft's vision of a networked world echoes that of other companies such as Sun Microsystems and Novell, which have talked about large servers storing information for individuals on the net without the need for a hard disk. Some of the company's "partners" yesterday welcomed .NET.

Marc Andreessen, the co-founder of Netscape, the internet browser company which was largely crushed by Microsoft, was one of the more surprising supporters. The building blocks of the new platform include the XML programming language and the Microsoft passport for extra security.

There was a slightly ironic note to Mr Gates's emphasis on ensuring the privacy and security of the new system yesterday as his own emails became a prime exhibit in the government's legal case against his company. The security provisions built into the .NET system would, he said, "put the user back in control".

Mr Gates said yesterday that many new services would be rolled out over the next year but that it would be 2002 before all of them were complete.